The present invention relates generally to a mechanism for adjusting the direction of a web of material in a packaging machine, and more specifically to an assembly for centering or tracking a web of film in an aseptic environment of a form-fill-seal packaging machine.
One type of packaging machine is a form-fill-seal packaging machine. Form-fill-seal packaging machines are typically utilized to package a product in a flexible container. To this end, form-fill-seal packaging machines are used to seal pharmaceuticals, foods, liquids, magazines, cosmetics, pre-boxed goods, and numerous other items in flexible containers. The form-fill-seal packaging machine provides an apparatus for packaging these and many other products in an inexpensive and efficient manner.
Pursuant to FDA requirements, certain pharmaceuticals packaged in form-fill-seal packages are traditionally sterilized in a post-packaging autoclaving step. The post-packaging step includes placing the sealed package containing the pharmaceutical in an autoclave and steam sterilizing or heating the package and its contents to a required temperature, which is often approximately 250xc2x0 F., for a prescribed period of time. This sterilization step operates to kill bacteria and other contaminants found inside the package, whether on the inner layer of film or within the pharmaceutical itself.
Certain packaged pharmaceuticals, however, cannot be sterilized in such a manner. This is because the intense heat required to kill the bacteria in the autoclaving process destroys or renders useless certain pharmaceuticals. As such, a different method of sterilization must be employed when packaging these types of pharmaceuticals.
One method of packaging heat sensitive pharmaceuticals is to first sterilize the pharmaceutical with a means other than intense heat, often through filtering, and then to package the pharmaceutical in an aseptic environment.
To date, the assignee of the present invention has developed several improvements in aseptic form-fill-seal packaging. Such improvements include at least: U.S. Pat. No. 4,761,197 (directed to an apparatus for sealing a web of film); U.S. Pat. No. 4,695,337 (directed to an apparatus and method for attaching a fitment to a web of film); U.S. Pat. No. 4,829,746 (directed to an apparatus for placing a web of film under tension); U.S. Pat. No. 4,888,155 (directed to an apparatus for sterilizing film and like packaging material); U.S. Pat. No. 4,744,845 (directed to an apparatus for splicing film together); and, U.S. Pat. No. 4,783,947 (directed to an apparatus for removing liquid and residue from a web of film).
Web tracking assemblies utilized in conventional form-fill-seal packaging machines (i.e., form-fill-seal packaging machines that do not include an aseptic packaging environment) are generally not suitable for use in an aseptic environment. For example, two conventional web tracking means are disclosed in U.S. Pat. No. 3,680,446, issued to James et al., and U.S. Pat. No. 5,833,106, issued to Harris. The ""446 patent issued to James et al. discloses a tracking system including a shiftable web guide roller having adjustable air cylinders mounted at its opposite ends for independently adjusting the ends of the roller (see FIG. 1 of the ""446 patent). The ""106 patent issued to Harris discloses an equalizing roll utilizing a common-axis shaft mounted horizontally on two bearings at its end for support, and a roller or sleeve mounted on the shaft. The sleeve has a single bearing mounted in the center of the sleeve with convex and concave portions that allows the sleeve to laterally rotate on the central bearing (see FIG. 5 of the ""106 patent). Such web tracking devices of the ""446 and ""106 patents are likely not appropriate for aseptic environments because of the number of moving parts and the areas for gathering particulate bacteria matter.
Thus, improvement in tracking the web of film as it enters the former in aseptic form-fill-seal packaging machines would be useful. To date, form-fill-seal packaging machines designed for aseptic packaging utilize a tracking assembly located adjacent the unwind, and outside the aseptic environment. This tracking assembly, however, is not located adjacent the former, but rather is located upstream of the ultimate package forming process. Thus, occasionally difficulties are encountered in attempting to track the film within the aseptic environment. As a result of this web-tracking limitation, much waste, inefficiency, and increased manufacturing costs are encountered by packagers in this industry. Specifically, when the web tracking is not balanced, and the web is not aligned through the former, each package that is created generally must be discarded due to improper overlap of the layers of film in the seal area. This may result in wasted film and wasted pharmaceutical material. It also may result in increased operator expense to observe the misaligned film, to select and discard the poorly formed packages, and to attempt to re-align the film. Further, severe cases of misaligned film may result in down time for the machine. All of the above increases the manufacturing costs of packaging such pharmaceuticals.
Thus, a means for tracking the web of film in the aseptic environment of a packaging machine is essential.
The web-centering apparatus of the present invention provides an assembly for tracking a web of material within an internal aseptic area of a form-fill-seal packaging machine. Generally, the web-centering apparatus comprises a support member, a tracking assembly, and an alignment mechanism. While the web-centering apparatus is located within the aseptic area of the packaging machine, certain components of the web-centering assembly are sealed off from the aseptic area in order to maintain the integrity of the aseptic environment.
According to one aspect of the present invention, the packaging machine has a former, a filler and a sealer located within the internal aseptic area of the packaging machine. The former forms bags from a web of material; the filler fills the bags with a substance; and, the sealer seals the bags to enclose the substance within the bags.
According to another aspect of the present invention, the support member is fixed to the form-fill-seal packaging machine within an interior aseptic environment of the form-fill-seal packaging machine, and the tracking assembly is rotatedly mounted to the support member in the aseptic environment of the form-fill-seal packaging machine. To provide for the mounting engagement between the support member and the tracking assembly, one of either the support member or the tracking assembly has a shaft member depending therefrom, and the other of either the support member or the tracking assembly has an engaging receptacle for the shaft member. The shaft member is seated in the engaging receptacle and pivots within the engaging receptacle. The pivoting of the shaft member provides angular displacement of the tracking assembly.
According to another aspect of the present invention, an engagement surface of each of the shaft member and the receptacle is sealed off from the aseptic environment of the form-fill-seal packaging machine.
According to another aspect of the present invention, a portion of the engaging surfaces between the shaft member and the receptacle are sealed off from the internal aseptic environment of the form-fill-seal packaging machine with a first gasket. A second gasket member seals off a second end of the receptacle.
According to another aspect of the present invention, the web tracking apparatus has a bearing surface between the pivot shaft and the receptacle. The bearing surface is sealed off from the aseptic environment with gaskets.
According to another aspect of the present invention, the tracking assembly comprises an engaging member and a roller member connected to the engaging member. The roller member is adapted to contact the web of material, and the engaging member pivots about the support member.
According to another aspect of the present invention, the tracking assembly is positioned at an angle with respect to the support member. The angle of the tracking assembly is modified when the tracking assembly is pivoted about the support member. Modification of the angle of the tracking assembly adjusts the flow path of the web of material.
According to another aspect of the present invention, the alignment mechanism comprises a first adjustment member, a mating second adjustment member, and an operator shaft. The first adjustment member is connected to the operator shaft, the second adjustment member is fixed to the tracking assembly, and the first and second adjustment members engage each other. The operator shaft controls any movement of the first adjustment member. Through movement of the first adjustment member, which engages the second adjustment member, the tracking assembly is pivoted.
According to another aspect of the present invention, the first adjustment member comprises a worm gear connected to the operator shaft, and the second adjustment member comprises a mating spur gear fixed to the tracking assembly. The spur gear is driven by the worm gear to effectuate pivotal rotation of the tracking assembly about the support member.
According to another aspect of the present invention, a clutch mechanism is removably connected to the alignment mechanism. The clutch mechanism engages the operator shaft and allows an operator outside of the aseptic interior environment of the form-fill-seal packaging machine to rotate the operator shaft and pivot the tracking assembly to adjust the tracking of the web of material.
According to another aspect of the present invention, the roller member of the tracking assembly comprises a shaft and a roller. The shaft is secured to the engaging member, and the roller is capable of rotating about the shaft. The roller member pivots with the tracking assembly about the support member when the tracking assembly is pivoted thereabout. Further, the roller member contacts the web of material.
According to another aspect of the present invention, the tracking mechanism is located in the internal aseptic area of the packaging machine immediately upstream of the former. The tracking mechanism contacts the web of material and pivots within the aseptic area of the packaging machine. Further, the tracking mechanism is connected to an external control unit that controls the pivoting of the tracking mechanism. And, the pivoting of the tracking mechanism alters an angle of contact between the tracking mechanism and the web of material to center the web of material entering the former.
According to another aspect of the present invention, a container for holding a pharmaceutical is manufactured in an aseptic form-fill-seal packaging machine having a web centering system made in accordance with the present invention.
According to yet another aspect of the present invention, a process for centering a web of material in an aseptic environment of a form-fill-seal packaging machine is provided utilizing the web centering system made in accordance with the present invention.
Accordingly, a web centering system made in accordance with the present invention provides an inexpensive, easily manufactured, and efficient assembly which eliminates the drawbacks associated with aseptic form-fill-seal packaging machines.
Other features and advantages of the invention will be apparent from the following specification taken in conjunction with the following drawings.